小学五年级递等式运算

3.8×5.4+2.7×2.4
=3.8×2.7×2+2.7×2.4
=2.7×(7.6+2.4)
=2.7×10
=27
或者
3.8×5.4+2.7×2.4
=3.8×5.4+5.4×1.2
=5.4×(3.8+1.2)
=5.4×5
=27

可以将5.4看成2.7*2；
3.8*5.4+2.7*2.4=2.7*(3.8*2+2.4)=2.7*10=27

2.4应该是5.4吧，你仔细看看
如是这样
有3.8*5.4+2.7*5.4
=（3.8+2.7）*5.4
=6.5*5.4
=35.1